Preparation of Nanocomposite-Based High Performance Organic Field Effect Transistor via Solution Floating Method and Mechanical Property Evaluation

Abstract

We demonstrate that using nanocomposite thin films consisting of semiconducting polymer, poly(3-hexylthiophene) (P3HT), and electrochemically exfoliated graphene (EEG) for the active channel layer of organic field-effect transistors (OFETs) improves both device performances and mechanical properties. The nanocomposite film was developed by directly blending P3HT solution with a dispersion of EEG at various weight proportions and simply transferring to an Si/SiO2 substrate by the solution floating method. The OFET based on P3HT/EEG nanocomposite film showed approximately twice higher field-effect mobility of 0.0391 cm2·V−1·s−1 and one order of magnitude greater on/off ratio of ~104 compared with the OFET based on pristine P3HT. We also measured the mechanical properties of P3HT/EEG nanocomposite film via film-on-elastomer methods, which confirms that the P3HT/EEG nanocomposite film exhibited approximately 2.4 times higher modulus (3.29 GPa) than that of the P3HT film (1.38 GPa), while maintaining the good bending flexibility and durability over 10.0% of bending strain and bending cycles (1000 cycles). It was proved that the polymer hybridization technique, which involves adding EEG to a conjugated polymer, is a powerful route for enhancing both device performances and mechanical properties while maintaining the flexible characteristics of OFET devices.

Fabrication of Wearable Transistor with All-Graphene Electrodes via Hot Pressing

“…The µ FET of the textile-OFET developed using the P3HT/EEG nanocomposite, as calculated from the transfer curve in Figure 10a, is 13.8 cm 2 V −1 s −1 , which is ~1.5 times amplified compared to the textile-OFET developed using a pure P3HT active channel layer (Table 1). Therefore, the electrical characteristic of amplification through EEG hybridization appears to be beneficial for the textile-OFET, as with the result of the previous research [22]. Hence, it can be concluded that the deposition of the active channel layer developed using the P3HT/EEG nanocomposite was completed successfully via the SFM, and the device developed using EEG electrodes (spray-coated EEG S/D and hot pressed EEG/textile gate electrode) operated well.…”

“…The SFM is a highly efficient deposition method, not only in terms of forming the well-crystalline polymer semiconductor channel in wearable devices, but also in terms of enhancing electrical properties and easily imparting new functions of the polymer semiconductor channel by combining the nanomaterials [21]. We completed the textile-OFET by applying the P3HT/EEG nanocomposite film using the SFM, which was optimized in a previous study [22] where the OFET devices fabricated using P3HT/EEG nanocomposite films with a mass ratio of 10:1 exhibited a nearly twice as high field-effect mobility compared to the OFETs developed using pristine P3HT, as well as showing an order of magnitude amplification of the OFET on-off ratio. Consequently, EEG was applied to all of the components of the textile-OFET, from the gate electrode and S/D electrodes to the active channel material.…”

Understanding the thermomechanical behavior of graphene-reinforced conjugated polymer nanocomposites via coarse-grained modeling

“…5c). 70 Expectedly, with different temperatures and side chain lengths, graphene fillers exerted the same enhancement effect, as depicted in Fig. S13 †…”

Assessment of the Optical Properties of a Graphene–Poly(3-hexylthiophene) Nanocomposite Applied to Organic Solar Cells

“…Several methods for the preparation of P3HT/G nanocomposites have been reported, including solution mixing and in situ polymerization [7,8]. In situ polymerization consists of mixing nanofillers with a liquid monomer or a precursor of a low molecular weight.…”

“…Polymerization is carried out by adjusting the temperature and time. It is a very effective method that allows carbon-based nanofillers to be dispersed uniformly in the matrix, thereby providing a strong interaction between them [8]. A representative SEM image of the P3HT/G nanocomposite is shown in Figure 2.…”